Monitor E172FPb - power light flashes

Rics

I accept your point about altering components however this was advised by one of our electronics designers, it may be worth pulling the transistors out and checking them again.

Rics and Nick

I'm going to attempt the exact same repair as was outlined in the beginning of the thread with the exact same components and board (Benq).  I'll let you know how it turns out.

Can't thank you guys enough for all the help.

Nov 5th=Bonfire night eh?

If this repair doesn't work can I throw my monitor on the blaze?

I'll bring a keg, that should show my gratitude properly :)

LG73

Good luck, hope it works for you, currently I am sitting infront of a borrowed 17" CRT.  Its horrible.

Nick,

Get the back off again for £ 5 or 6 its got to be worth a shot, my electronics guys advised not to mod the new transistors.

xOD,

When I contacted benq they couldn't sell me any components but offered me a repair to the board. You could try contacting their service department for some advice, you might be lucky and wangle a schematic from them (long shot I know)

LG73,

Lets get the batting average up, hope it works especially if there is the offer of a keg.

Rics

I was going to give it another shot.

My "electronics expert" who also carried out the transplant just happens to be my boss, and the Managing Director! so I more or less had to accept his advice.  I plan to take the monitor back to work tomorrow and check to see if the transistors have failed.

Cheers

Nick

Rics

Should be done tomorrow although the guy who is doing the actual repair for me (my who step dad works for an engineering firm and has access to the needed tools and expertise) is balking a little at the size of the replacement transistors and the thought of modifying the cover to accomodate their size (the D44H8's).  I think he's just being overly cautious but is there any danger of introducing interference by cutting into the shielding (the cover)?

And just to cover the bases a little...  is it possible to visually discern whether a back light has bought the farm?

Hope fully tomorrow night I'll be viewing this thread through an lcd :)

Thanks again

Well, I figured out what was wrong. I recieved some false information regarding the need for insulating the heatsinks on the new transistors. They absolutely must be insulated!!!!! I just stuck some electrical tape on the chassis, put it back together and everything works!! I just hope it lasts. I got my monitor for free from a friend who was gonna throw it away. Just a couple bucks and I have a working LCD. I am thrilled!!

Thanks Everyone, I would buy you all a beer if I could!!

x0D

The latest update:-

I now have all the transistors out and they are all OK, one had got "a bit warm" and had affected the capacitor next to it but this also was fine, we also took out all the capacitors but no problem there.  My electronics expert (boss!) hasn't given up hope and the saga has not yet ended up in a wheely bin.

The fate of the E172FPb hangs in the balance.

I will let you all know

Something interesting happened to my monitor. I set my resolution to 1280 x 1024 as suggested by the monitor ( in the setup ). A half an hour later, the monitor appeared to be off. I hit the power button and the screen flashed back up for about 5 seconds and then went black and kept doing so . I turned it off and took a shower and when I came back, I hit the power button again and everything came up fine. I have since reset my resolution lower and it has been working great ever since. I suspect an overheating problem. Instead of modifying the chassis during the repair, I chose to modify the transistors instead so the lack of dissipation from the modifed heatsinks could be the problem. I am considering making custom heatsinks to circumvent this issue. Has anyone else had similar problems? What modification methods have you all used?

Thanks,

x0D

Something interesting happened to my monitor. I set my resolution to 1280 x 1024 as suggested by the monitor ( in the setup ). A half an hour later, the monitor appeared to be off. I hit the power button and the screen flashed back up for about 5 seconds and then went black and kept doing so . I turned it off and took a shower and when I came back, I hit the power button again and everything came up fine. I have since reset my resolution lower and it has been working great ever since. I suspect an overheating problem. Instead of modifying the chassis during the repair, I chose to modify the transistors instead so the lack of dissipation from the modifed heatsinks could be the problem. I am considering making custom heatsinks to circumvent this issue. Has anyone else had similar problems? What modification methods have you all used?

Thanks,

x0D

That sounds very similar to what I was seeing.

My boss suspects that the culprit may be the tubes pulling extra current and causing the transistors to fail.